Solve for $x$ : $2\sqrt{x} - 7 = 10\sqrt{x} + 6$
Solution: Subtract $2\sqrt{x}$ from both sides: $(2\sqrt{x} - 7) - 2\sqrt{x} = (10\sqrt{x} + 6) - 2\sqrt{x}$ $-7 = 8\sqrt{x} + 6$ Subtract $6$ from both sides: $-7 - 6 = (8\sqrt{x} + 6) - 6$ $-13 = 8\sqrt{x}$ Divide both sides by $8$ $\frac{-13}{8} = \frac{8\sqrt{x}}{8}$ Simplify. $-\dfrac{13}{8} = \sqrt{x}$ The principal root of a number cannot be negative. So, there is no solution.